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The progress status of jet-grouting construction during the construction phase is difficult to verify and even after the completion of construction, it can be verified only by empirical methods. This study attempted to recreate a realistic simulation result of the middle-pressure jet-grouting method by establishing a computer-aided engineering (CAE) system from the planning/design stage of the ground model and verifying the validity of the construction process after the model was analyzed by the moving particle semi-implicit (MPS) method. The governing parameters for the ground were determined by the MPS simulation of the unconfined compression test. The construction simulation was analyzed and the results were validated by visual confirmation of the related phenomena, such as the soil-improved body formation and mud discharge. To verify the accuracy of the mud discharge phenomenon, three different probe regions were set above the model ground and the amount of mud discharge generated in each region was computed before drawing an overall conclusion of the study. A soil-improvement body of approximately 0.38 m3 was observed to have formed at the end of the study and the highest mud discharge particle number measured, for instance, was 896. This study is expected to serve as a guideline for further studies on simulation-based research.

Grouting is an effective method to improve the integrity and stability of fractured rocks that surround deep roadways. After years of research and practice, various theories and a complete set of grouting technologies for deep roadways with fractured rocks have been developed and are widely applied in Chinese coal mining production. This paper systematically summarizes and analyzes the research results concerning the theory, design, materials, processes, and equipment for the grouting and reinforcement of fractured rocks surrounding deep roadways. Specifically, in terms of grouting methods, pregrouting, grouting‐while‐excavation, and postgrouting methods are explored; in terms of grouting theory, backfill grouting, compaction grouting, infiltration grouting, and fracture grouting theories are studied. In addition, this paper also studies grouting borehole arrangement, water‐cement ratio, grouting pressure, grouting volume, grout diffusion radius, and other grouting parameters and their determination methods. On this basis, this paper explores the physical and mechanical properties of organic and organic‐inorganic composite grouting materials, and assess grouting reinforcement quality testing methods and instruments. Taken as the field cases, the application of pregrouting in front of heading faces, grouting‐while‐excavation, and postgrouting in the Kouzidong coal mine are then introduced, and the effects of the grouting reinforcements are evaluated. This paper proposes a development direction for grouting technology based on problems existing in the grouting reinforcement of fractured rocks surrounding deep roadways. Grouting theories and technologies for the reinforcement of fractured rocks surrounding deep roadways are reviewed. Field cases of the application of pregrouting in front of heading faces, excavation‐while‐grouting, and postgrouting in the Kouzidong coal mine are introduced. A development direction for grouting technology is proposed based on problems existing in the grouting reinforcement of fractured rocks surrounding deep roadways. Highlights Grouting theories and technologies for the reinforcement of fractured rocks surrounding deep roadways are reviewed. Field cases of the application of pregrouting in front of heading faces, excavation‐while‐grouting, and postgrouting in the Kouzidong coal mine are introduced. A development direction for grouting technology is proposed based on problems existing in the grouting reinforcement of fractured rocks surrounding deep roadways.

The mining depth of most coal mines in North China has exceeded 1 km. The high seepage water pressure caused by high ground stress leads to the increasingly serious threat of water disaster in the mine. To explore the relationship and mechanism between water inrush from deep mining floor and grouting prevention, single-level grouting and multi-level cooperative grouting methods were carried out in Ordovician limestone confined aquifer of coal seam floor in Xingdong coal mine. Meanwhile, the temporal and spatial characteristics of rock fracture in the floor of deep mining face are revealed through the law of rock fracture microseismic. It is noteworthy that the occurrence time of water inrush and microseismic events have lag characteristics, that is, the occurrence time of microseismic events is earlier than that of water inrush. The multi-level cooperative grouting method can effectively control the non-uniform dissolution Ordovician limestone aquifer in-plane and vertical plane. Furthermore, single-level grouting and multi-level cooperative grouting methods are assumed to be unstable grouting and stable grouting. Besides, the flow pattern transformation characteristics of Ordovician limestone water in unstable to stable grouting are simulated by the finite element method. The results show that the energy inoculation level of fracture expansion around the aquifer decreases after stable grouting reinforcement. In other words, the multi-level cooperative grouting method can effectively strengthen and fill the water inrush channel and reduce the damage of high osmotic pressure to the aquiclude. It is of great significance to reduce the probability of water inrush in deep coal seam and ensure the mining safety of deep coal seam.HighlightsThe Ordovician limestone rock mass damage and dissolution are characterized by layered failure and non-uniform dissolution in horizontal and vertical directions.The occurrence time of water inrush and microseismic events in Xingdong mining area have the lag characteristics.A continuous multi-level collaborative grouting method in karst aquifer is proposed through segmenting, sequencing, and grouting pressure strengthening.Multi-level cooperative grouting method in Ordovician limestone aquifer with high water pressure and uneven dissolution can effectively strengthen and fill the water inrush channel and reduce the probability of water inrush.

With the rapid economic development in recent years, the development of civil engineering has become more and more rapid. Therefore, in order to ensure the quality of civil engineering construction, it is necessary to reasonably modify the grouting construction method of civil engineering construction. By improving the grouting construction method, the quality of civil engineering can be guaranteed as much as possible. Therefore, this article mainly analyses and discusses the application of grouting technology in civil engineering construction. Through the analysis of the importance of grouting technology in civil engineering construction, we can further enhance the construction unit’s attention to grouting technology and promote the effective development of grouting construction technology in civil engineering.

Post-grouting is an active reinforcement technique that can significantly enhance the bearing performance of bored piles. This study conducted field tests on three in situ test piles using tip grouting, side grouting, and combined tip-side grouting. Based on the analysis of static load test data, the improvement effects of different grouting methods on the vertical bearing behavior of the piles were quantified. In situ tests were then performed to elucidate the reinforcement mechanisms of various post-grouting techniques on the pile foundations. Based on the validated finite element model, the study explored the influence of key grouting parameters on the bearing performance of grouted piles. Analysis of the test data shows that all grouting methods improved the vertical bearing capacity of bored piles. The positive effect of tip grouting was more pronounced than that of side grouting. Furthermore, in the clay layer of the soft soil region, side grouting primarily manifested as splitting grouting, while tip grouting formed a hardened grout bulb at the pile tip through cementation and solidification, thereby significantly enhancing the mobilization of the pile tip bearing capacity. Finite element model analysis shows that, in terms of enhancing the bearing capacity of the pile, expanding the grout diffusion range is more effective than increasing the grout material strength.

The major focus of this study was determining the effectiveness of new construction specifications regarding the method of cement grout injection for the jet grouting system (high-pressure injection stirring method), with the objective of developing a sustainable ground improvement method. The recent innovative jet grouting techniques allow for improvement at middle pressure, but the mud discharge amount is drastically increased. This produces a serious environmental and financial burden during the disposal of mud discharge. This study attempts to develop a sustainable jet grouting method. The simulation model was prepared by the 3D AutoCAD software, and the analysis was conducted using the moving particle semi-implicit method (MPS method). The study focused on the changes that occurred in the mixing ratio of cement slurry and soil due to the changes made in cement milk spraying during the construction phase and compared it with the traditional method of cement milk spraying. All other construction parameters were kept the same for both cases, and the comparison result shows that the modified construction specification provides a denser and larger improved soil body than the traditional method. Furthermore, the density of the number of particles was determined at the upper, middle, and lower portions of the improved body for comparison.

Prepacked aggregate concrete (PAC) is made by placing coarse aggregates of various sizes into a formwork and then filling the voids between coarse aggregate and grout. The mechanical performance of PAC is dominated by the compactness due to grout filling, but few study considered the pouring methods and grout performance synchronously. The coupled effect of pouring methods and grout performance on the compactness of PAC is investigated in this study. The results show that the gravity pouring method is only suitable for grouts with good flowability. The pump pouring method is more widely used. It can be adapted to grout with poorer fluidity and coarse aggregate with greater apparent density. The ultrasonic pulse velocity test method provides a relatively accurate evaluation of the compactness of PAC. Furthermore, due to the enhanced mechanical properties of PAC, the filed application potential in the preparation of steel tube concrete columns has also been confirmed, where the results exhibited that PAC based steel tube concrete contributed to an enhanced ductility and autogenous shrinkage.

This study focused on the middle-pressure jet grouting method, which has a complicated development mechanism for the columnar soil-improved body, with the aim of establishing a computer-aided engineering (CAE) system that can simulate the performance on a computer. Furthermore, in order to confirm the effect of middle-pressure jet grouting with mechanical agitation and mixing, a comparative analysis was performed with different jet pressures, the development situation was visualized, and the performance of this method was evaluated. The results of MPS-CAE as one of the CAE systems showed that the cement slurry jet ratio in the planned improvement range, including the periphery of the mixing blade, by the middle-pressure jet grouting together with the mechanical agitation and mixing was increased and a high quality columnar soil-improved body was obtained. It is expected that the introduction of CAE will contribute to the visualization of the ground, and that CAE will be an effective tool for the visual management of construction for ground improvement and the maintenance of improved grounds during the life cycle of the ground-improvement method.

One of the soil improvement methods is using soil-cement columns, and one of the most common methods of implementing these columns is the Jet grouting method. In this article, the performance of Jet grouting columns in soil improvement and excavation wall stabilization is investigated in a project located in Chalous, north of Iran, by implementing several experimental soil-cement columns in real scale at depths of 4, 8, and 15 meters and diameter of 80 cm. By comparing the soil settlement before and after the improvement, it was found that the average settlement, which was in the range of 186 mm before the improvement, reached about 68 mm after the improvement using the jet grouting method. It has been observed that the settlement of the foundation has been significantly reduced after improving the ground with soil-cement columns. On the other hand, the results of this study showed that this method has also been very effective in stabilizing the excavation walls. The maximum displacement of the crest of the wall is about 3.4 cm, and the maximum settlement behind the wall is limited to 12 mm.

This study conducted 1-G shaking table tests to compare methods of reducing liquefaction damage during earthquakes. The sheet pile and grouting methods were selected as applicable to existing structures. Model structures were manufactured for two-story buildings. A sine wave with an acceleration of 0.6 g and a frequency of 10 Hz was applied to the input wave. Certain experiments determined the effect of various sheet pile embedded depth ratios and grouting cement mixing ratios on reducing structural damage. The results confirmed that when the sheet pile embedded depth ratio was 0.75, the structure’s settlement decreased by approximately 79% compared to the control model. When the grouting cement mixing ratio was 0.45, the structure’s settlement decreased by approximately 85% compared to the untreated ground. In addition, the sheet pile method suppressed the increase in pore water pressure compared to the grouting method but tended to interfere with the dissipation of pore water pressure after liquefaction occurred. Additionally, comparing the effect of each method on reducing liquefaction damage revealed that the grouting method resulted in less settlement, rotation of the structure, and pore-water-pressure dissipation than the sheet pile method. Overall, the grouting method is more effective in reducing liquefaction damage than the sheet pile method. This study forms a basis for developing a liquefaction-damage reduction method applicable to existing structures in the future.